The efficacy of pre-emptive
analgesia for
phantom limb pain is still unclear. It is generally accepted that pre hyphen;
amputation pain increases the incidence of phantom and stump
pain, even if pre-emptive
analgesia is performed before and during surgery and in the postoperative period. Two cases of traumatic upper limb
amputations are described here with no pre-existing
pain. Both received similar antinociceptive treatment by continuous block of the brachial plexus through infusion of
ropivacaine 0.375% at 5 ml/h for 10 days. Treatment of case 1 was initiated immediately after surgery; however, this amputee developed intensive
phantom limb pain which persisted at 6 months. Early use of the
prosthesis after surgery was not possible for this patient. The intensity of
phantom limb pain in case 2 decreased significantly after 6 months, even though
brachial plexus blockade was not started until 5 weeks post-
trauma. This patient used a functional
prosthesis intensively beginning early after
amputation. Serial magnetoencephalographic recordings were performed in both patients. Only case 2 showed significant changes of cortical reorganization. In case 1 markedly less cortical plasticity was found. A combination of relevant risk factors such as a painful
neuroma, behavioural and cognitive coping strategies and the early functional use of
prostheses are discussed as important mechanisms contributing to the development of
phantom pain and cortical reorganization.